Biomedical subjects

T Morimoto

Publications and source records attributed to T Morimoto.

At least 415 records · Page 23Linked to original sources

PubMed1993

Juvenile gigantomastia: report of a case.

Juvenile gigantomastia in a 12-year-old girl was treated by a bilateral reduction mammoplasty with free transplantation of the areolae and nipples and the removal of 3,980 g of breast tissue. Regrowth of the residual breast tissue has been suppressed by the administration of tamoxifen, an antiestrogen drug, since the surgery. This case was positive for estrogen receptors (ER) by the dextran-coated charcoal method, while tissue staining for ER and estradiol resulted in a darker staining of the epithelial contents, especially of fibroadenoma-like nodules, using an immunocytochemical assay. It is thus suggested that the etiology of this disease might be related to a local hypersensitivity to estrogen.

Breast Diseases↗

PubMed1993

The coexistence of lobular carcinoma in a fibroadenoma with a malignant phyllodes tumor in the opposite breast: report of a case.

It is very unusual for a carcinoma of the breast to coexist with a phyllodes tumor, or for a carcinoma to arise within a fibroadenoma. We present herein an extremely rare case of lobular carcinoma in situ arising in a fibroadenoma, associated with a malignant phyllodes tumor in the opposite breast. A 49-year-old woman was admitted to our hospital with a large mass in the right breast and a small mass in the left breast. Microscopic examination of biopsy materials revealed a malignant phyllodes tumor in the right breast and a fibroadenoma in the left breast, for which a right standard radical mastectomy and left lumpectomy were performed. Microscopic findings of the material excised from the left breast showed the presence of multiple lobular carcinoma in situ within the tumor mass of the fibroadenoma. However, histological examination did not detect any metastasis to the bilateral axillary lymph nodes. To our knowledge this is the only such case ever to be reported in Japan.

Adenofibroma↗

PubMed1993

Frequency of spontaneous p53 mutations (CpG site) in breast cancer in Japan.

Sixty-five tumors of invasive ductal carcinoma of the breast were examined for p53 alteration by the reverse transcription-polymerase chain reaction-single strand conformation polymorphism (RT-PCR-SSCP) method and sequencing analysis. In total, 16 samples (24.6%) showed p53 gene alteration. Sixteen of these alterations were evaluated by sequencing analysis, and 15 showed missense point mutations while one showed a 9-base pair deletion. In the 15 point mutations, G:C to A:T transitions constituted the majority (53%), and five tumors (33%) had a transition at the CpG site, which are mutational patterns not commonly found in breast tumors from Europe and America. On the other hand, there were no G:C to T:A transversions in our cases, which were frequently observed transversions in Europe and America. These p53 mutation patterns in breast cancer in Japan are not similar to those in Europe and America reported by Hollstein et al. and Coles et al.. These findings suggest that there are some differences between mechanisms of breast cancer in Japan and in Europe and America.

Adult↗

PubMed1993

The effect of acetylcholinesterase inhibitor (SDZ ENA 713) for r-CBF and focal cerebral ischaemia.

The purpose of the present study was to examine the effect of Acetylcholinesterase inhibitor (AChEI) on r-CBF (group A) and its protecting effect on focal ischaemic cell damage (group B). The pial arterial diameter and the r-CBF were measured with a width analyzer and with a laser Doppler flowmeter through a cat cranial window on the ectosylvian gyrus. The ischaemic area was measured histologically. We used intravenous injection of AChEI([-])(S)-N-ethyl-3-[(1-dimethyl- amino)ethyl]-N-methyl-phenylcarbamate, SDZENA 713, Sands Pharmacy) to block AChE. Twenty minutes after injection AChEI (0.6 mg/kg) the pial arteriole dilated 108.5 +/- 1.8% and the r-CBF increased 115.4 +/- 2.6%. The pial arteriole dilated maximally to 137.6 +/- 6.5% at 120 minutes after injection and the r-CBF increased maximally to 137.1 +/- 19.5% at 60 minutes after injection. The protecting effect was evaluated using cats and 1 hour of occlusion of the middle cerebral artery (MCA). Twenty minutes after injection of AChEI, the pial arteriole dilated to 116.7 +/- 2.4% and the r-CBF increased to 111.9 +/- 2.6% significantly. During MCA occlusion the r-CBF decreased to 24.7-41.4% in group B and 25.1-32.6% in sham group (group C). The pial arteriole dilated 145.0-184.0% in group C and 150.7-171.6% in group B during MCA occlusion and 30 minutes after reperfusion the pial arteriole returned to 120.0 +/- 3.3% in group C and 123.4 +/- 11.3% in group B. There were no significant changes in the r-CBF and the vessel diameter between group B and C during the 2 hours after reperfusion.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetylcholine↗

PubMed1993

Electrical impedance in the lower limbs of patients with Duchenne muscular dystrophy: a preliminary study.

Electrical impedances were measured, at a range of frequencies from 2 to 200 kHz, in the lower limbs of nine patients with Duchenne muscular dystrophy and 12 normal subjects. The specific admittance was calculated from the impedance, based on the assumption that the shape of the part of the limb measured is a truncated cone. Curve-fitting to the admittance locus on the complex plane gave the intracellular and extracellular resistances and the membrane capacitance. The intracellular resistance was higher and the membrane capacitance was lower in the patients than in the normal subjects. The membrane capacitance in the normal subjects increased with age. In the patients, the membrane capacitance decreased, and the intracellular resistance increased with the stage of disability, which was assessed by a physician. These experimental results agree well with the theoretical explanation, which uses simplified spherical models to represent living tissue.

Adolescent↗

PubMed1993

An electromyographic study of whether the digastric muscles are controlled by jaw-closing proprioceptors in man.

Whether in the oral system the digastric muscles (which lack muscle spindles) are under the control of proprioceptive information from the masseter muscles (which contain muscle spindles) was investigated by analysing whether and how the masseters and digastrics showed coordinated behaviour during a static, forceful bite. Subjects were asked to maintain a 100-N force for 15 s with and without visual guidance; bite force exerted, and masseter and digastric electromyograms (EMGs) were recorded. Under visual guidance all subjects co-contracted their digastric muscles during the isometric bite. They held the force for a short time, followed by periods with fluctuations (peak-to-peak force amplitude about 15-20 N). Fluctuations in bite force correlated with the masseter EMGs, the maximum in the correlogram occurring at about -50 ms with the force lagging the masseter. In 75% of the subjects a significant periodic component in the masseter and in the force spectra was found at about 4 Hz. This was also seen in the amplitude spectra of the forces, which showed in 80% of the subjects a significant elevation between 7-10 Hz as well. No correlation between the digastric EMGs and the bite forces, and between the EMGs of masseter and digastric could be detected. Spectra of digastric EMGs showed no prominent maxima. When subjects were deprived of visual feedback, maxima at -50 ms in the cross-correlation functions of the masseters and the forces were reduced considerably; periodicities of +/- 250 ms disappeared.(ABSTRACT TRUNCATED AT 250 WORDS)

Bite Force↗

PubMed1993

The effect of dehydration level on the NaCl concentration chosen by rats.

The relationship between the level of dehydration (3%, 6%, and 8% body weight) and the preference for water and saline in the rehydration were assessed in rats for 15 h. At the 6% and 8% dehydration levels, rats provided with tap water and 0.9% NaCl solution simultaneously consumed more water than NaCl solution (calculated Na concentration was about 57 mEq/l) within 3 h and then consumed more NaCl solution than water (about 116 mEq/l). The shift of the Na concentration of fluid occurred when about 107% of lost cations and 82% of lost fluid were regained. Urine output and urinary Na output were about 14% of the ingested fluid during the initial 4 h; after that, the output was in amounts almost equal to the ingestion. However, the 3% dehydrated rats consumed almost equal amount of tap water and NaCl solution (about 68 mEq/l) throughout the 15 h. The result indicates that at more than 3% dehydration level, rats initially choose hypotonic NaCl solution, and the volume loss of body fluid is then regained by the consumption of almost isotonic Na solution.

Animals↗

PubMed1993

Suprasellar embryonal carcinoma which developed ten years after local radiation therapy for pineal germinoma.

We recently encountered a case of suprasellar embryonal carcinoma which developed 10 years after local radiation therapy for pineal germinoma. This 29-year-old male was admitted because of abnormal behavior, disturbed consciousness, and increased intracranial pressure. Computed tomography and magnetic resonance imaging disclosed a tumor spreading from the suprasellar region to the third ventricle and the anterior horn of the left lateral ventricle, accompanied by fresh hemorrhage within the tumor. He underwent subtotal removal of the tumor, followed by chemotherapy with cisplatin and etoposide. The tumor was histologically rated as embryonal carcinoma with differentiation into yolk sac tumor and choriocarcinoma.

Adult↗

PubMed1993

Arterial ketone body ratio and glucose administration as an energy substrate in relation to changes in ketone body concentration after living-related liver transplantation in children.

Changes in the arterial ketone body ratio (AKBR [acetoacetate/3-hydroxybutyrate]), which reflect the redox state of the liver mitochondria (NAD+/NADH), as well as those in total ketone body concentration (TKB) and blood glucose level were studied in 30 living-related liver transplantations (LRLT) performed in pediatric patients at Kyoto University Hospital from June 1990 to January 1992. AKBR increased to over 1.0 within 6 hr after reperfusion of the graft in 11 cases (37%), within 12 hr in 7 (23%), on POD 1 in 8 (27%), and on POD 2 in the remaining 4 cases (13%). TKB significantly increased while AKBR remained below 0.7 (266 +/- 40 mumol/L), but it significantly decreased in accordance with the recovery of AKBR above 1.0 (61 +/- 6 mumol/L). This indicates the change in the predominant energy substrate for hepatic mitochondria from fatty acid to glucose during the AKBR recovery process. In 6 cases, the AKBR transiently decreased to below 1.0 after initial recovery concomitant with the fall in blood glucose level and the increase in TKB. However, the AKBR was rapidly restored to over 1.0 again immediately after the glucose administration was increased. This suggests that glucose administration to maintain blood glucose level between 150 and 250 mg/dl is essential for the AKBR recovery above 1.0 that accompanies the normalization of graft metabolic functions, and that, along with the postoperative minimal increase in serum enzymes and favorable outcome of the transplant with no incidence of a primary nonfunctioning graft, the prompt and successful recovery of AKBR reflects the expected high viability of the graft in our LRLT cases.

Adolescent↗

PubMed1993

Effect of mass screening for breast cancer from the aspect of psychosocial assessment of the quality of life.

To assess the quality of life (QOL) in patients with breast cancer receiving mass screening, a collaborative matched case-control study was conducted in nine hospitals throughout Japan. A total of 122 patients detected by mass screening (study group) and 226 patients found in out-patient clinics (control group) were assessed psychosocially on the basis of questionnaire information. The incidence of patients with early stage breast cancer was significantly higher in the study group than in the control group (P < 0.05). Chest wall pain was observed in 35.2% of the study group and in 46.5% of the control group (P < 0.05). Although control patients were more optimistic than study group patients, disturbed daily life and anxiety about recurrence were a little more frequent in the former group than in the latter. In particular, shoulder stiffness was frequently seen in the control group (P < 0.05). Early detection and information do not create anxiety in mass screening patients (P < 0.01). We should recommend mass screening to patients to detect early stage breast cancer and provide better QOL.

Activities of Daily Living↗

PubMed1993

An evaluation of mass screening using fecal occult blood test for colorectal cancer in Japan: a case-control study.

There is as yet no firm evidence showing that mass screening for colorectal cancer using fecal occult blood tests (FOBTs) reduces the mortality from this cancer. Therefore we evaluated the effectiveness of the screening by a case-control study in Miyagi Prefecture, Japan. The study included as case subjects 28 individuals who had died from colorectal cancer and had had an opportunity to participate in the mass screening before the date of diagnosis as colorectal cancer, and 3 controls for each case subject randomly selected from residents who were alive on the date of death of case subjects and matched by sex, age (within 3 years) and living area using residential files. For each set, i.e., a case subject and 3 controls, screening histories before the date of the diagnosis of the case as colorectal cancer were examined. Both the case subjects and the controls who had participated in the screening at least once within 3 years before the date of diagnosis of the case were classified as "screened." The 28 case subjects consisted of 12 males and 16 females (average age: 60.8 years). The odds ratio of death from colorectal cancer for the screened versus the non-screened persons was 0.24 (95% confidence interval = 0.08-0.76) by the Mantel-Haenszel method. The present study suggests that mass screening using FOBTs for colorectal cancer significantly reduces the mortality from this cancer epidemiologically.

Aged↗

PubMed1993

Difficulty in removing a percutaneous central venous catheter inserted from a peripheral vein.

Two girls with acute lymphocytic leukemia (ALL) are reported. There were difficulties in removing their central venous catheters inserted from a peripheral vein. One girl required surgery under general anesthesia for the removal. The other patient received continuous infusion of low dose urokinase from a distal peripheral vein. The residual catheter was then removed successfully.

Adolescent↗

PubMed1993

Effects of LP-805, a newly developed vasodilator, on myocardial metabolism in ischaemic dog hearts.

The effects of LP-805, a newly developed vasodilator, on changes in the myocardial energy and carbohydrate metabolism induced by ischaemia were studied in open-chest anaesthetized dogs. Ischaemia was induced by ligating the left anterior descending coronary artery for 3 min. The myocardial energy stores were depleted, and the levels of glycolytic intermediates were altered 3 min after the onset of ischaemia. Energy change potential was decreased, and ([G6P] + [F6P])/[FDP] and [lactate]/[pyruvate] ratios were increased by ischaemia. These findings indicated that the myocardial metabolism was converted from an aerobic to an anaerobic type by ischaemia. LP-805 (10, 30, or 100 micrograms kg-1) was injected intravenously 5 min before the onset of ischaemia. LP-805 prevented the myocardial energy depletion and alterations of myocardial carbohydrate metabolism due to ischaemia, indicating that it appeared to convert the anaerobic metabolism back to aerobic metabolism in the ischaemic myocardium. In conclusion, LP-805 may reduce the ischaemic influence on the myocardium.

Adenine Nucleotides↗

PubMed1993

Coordination of cortically induced rhythmic jaw and tongue movements in the rabbit.

1. Rhythmic movements of the jaw, tongue, and hyoid that were induced by stimulation of the cortical masticatory area (CMA) were recorded cineradiographically in the anesthetized rabbit. Jaw movements were also recorded by a laser position detector. 2. The evoked jaw movements were classified into four types: small circular (type A), large circular (type B), large vertical (type C), and crescent-shaped (type D). Among these, types B and D resembled the jaw movements of the food transport cycle and those of the chewing cycle in a masticatory sequence. 3. Each type of jaw movement was associated with a particular pattern of tongue and hyoid movements. In general, the tongue protruded during jaw opening and retracted during jaw closure. The hyoid generally moved upward and forward during jaw opening but downward and backward during jaw closure. 4. Electromyograms (EMGs) were recorded from jaw muscles [masseter (Ma) and digastric (Di) muscles], extrinsic tongue muscles [styloglossus (Sg) and genioglossus (Gg) muscles], and hyoid muscles [sternohyoid (Sh) and geniohyoid (Gh) muscles] during cortically induced rhythmic jaw and tongue movements (CRJTMs). These muscles were classified into two groups: group 1 was activated mainly in the jaw opening phase, and group 2 was activated mainly in the jaw closing and power phases. The Di, Gg, and Gh were included in the former, and the Ma, Sg, and Sh were included in the latter. 5. The timings of EMG activation to a jaw movement cycle were relatively constant for the muscles of group 1, irrespective of the types of CRJTMs, whereas those for the muscles of group 2 altered considerably with the different types of CRJTMs. 6. Relationships of the integrated muscle activity between the Di and Gg and between the Di and Gh were significant, whereas those between the Ma and Sg and between the Ma and Sh were not. 7. When a small strip of polyurethane form of various degrees of hardness was inserted between the opposing molars during CRJTMs, EMG activity of the muscles of group 2 increased with the hardness of the strip. On the other hand, EMG activities of the muscles of group 1 were less affected by the same intraoral stimuli. 8. Two conclusions were reached: first, physiological properties of the CRJTMs and cortically induced rhythmic movements of the hyoid were essentially similar to those observed in natural mastication. This fictive mastication might thus be regarded as a suitable model for simulating natural mastication.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

PubMed1993

Structural reorganization of the rough endoplasmic reticulum without size expansion accounts for dexamethasone-induced secretory activity in AR42J cells.

A striking reorganization of the rough endoplasmic reticulum (RER) from a tubulo-vesicular (TV-RER) to a stacked cisternal (SC-RER) configuration was observed when the secretory activity of AR42J cells, a cell line derived from a rat pancreatic acinar carcinoma, was induced by dexamethasone. Treatment with 10 nM dexamethasone resulted in a 6.6-fold increase in the intracellular and a 4.6-fold increase in the secreted amylase activity, respectively. On the basis of the morphometric analysis of thin-section electron micrographs it has been previously reported that this increase in secretory activity is accompanied by a 2.4-fold or 30-fold increase in the size of the RER. We have developed a new biochemical method to determine the size of the RER by quantifying the membrane-bound ribosomes. Using this procedure we did not detect any change in the size of the RER after induction of an active secretory state in AR42J cells. Electron microscopic observation showed the predominance of SC-RER in dexamethasone-treated cells compared to the abundance of TV-RER in control cells. Laser scanning confocal microscopy showed a patchy distribution of ER staining in dexamethasone-treated cells compared to more basal localization in control cells. On the basis of our observations we conclude that in AR42J cells the increase in secretory activity induced by dexamethasone is accompanied by a reorganization of the RER rather than by an increase in ER surface area, as reported by others. Our results suggest that SC-RER is a biosynthetically more efficient form of the RER, which is found predominantly in actively secreting cells.

Amylases↗

PubMed1993

Auto-growth inhibitory substance from the fresh-water cyanobacterium Phormidium tenue.

An extract of the cyanobacterium P. tenue showed a significant inhibitory effect on its own growth. Bioassay-directed fractionation has led to the identification of the auto-growth inhibitory substance as a mixture of fatty acids. Unsaturated fatty acids such as linoleic and linolenic acids appear to be predominantly responsible for the auto-growth inhibitory effect.

Cyanobacteria↗

PubMed1993

Effect of labor and prostaglandins on phenylethanolamine N-methyltransferase in human fetal membranes.

Biochemical investigations have shown the presence of the enzyme phenylethanolamine N-methyltransferase (PNMT), which converts norepinephrine (NE) to epinephrine (E) in human pregnant tissues, e.g. myometrium and fetal membranes. The enzymatic activity of PNMT in myometrium is known to decrease during labor. In the present study, PNMT activity in chorio-decidua was measured and the effect of labor and prostaglandins (PG) on PNMT activity was determined. A cytosol fraction of chorio-decidua was incubated with [14C]-S-adenosyl-L-methionine and normetanephrine for 60 min to measure PNMT activity. Fetal membranes were obtained at elective Cesarean section and normal vaginal delivery from full term pregnant women, and the activity of PNMT in chorio-decidua was compared. Significantly lower activity in chorio-decidua obtained from normal vaginal delivery than that from elective Cesarean section was observed. The concentration of 13, 14-dihydro-15-keto-prostaglandin F2 alpha (DHK-PGF2 alpha) in amniotic fluid obtained at normal vaginal delivery were measured by RIA, and the relationship of the DHK-PGF2 alpha level to PNMT activity was studied. There was a significantly negative correlation between the concentration of DHK-PGF2 alpha in amniotic fluid and PNMT activity in chorio-decidua. When various concentrations of PGF2 alpha were pre-incubated with mined chorio-decidua for 2 h, PNMT activity was decreased in a dose dependent manner. These results indicated that PGF2 alpha might affect the bioconversion of NE to E in fetal membranes. The presence of this enzyme in fetal membranes may play an important role in regulating the concentration of catecholamines during pregnancy and parturition.

Dinoprost↗

PubMed1993

Mid-term results of bilateral internal thoracic artery grafting.

Forty patients underwent coronary revascularization using bilateral internal thoracic artery (ITA) grafts between 1988 and 1992. A total of 111 coronary grafts were performed, or an average of 2.8 grafts per patient. Each patient received bilateral ITA grafts, and in 20 patients an additional 29 grafts were constructed with 18 autologous veins and 11 gastroepiploic arteries. The right ITA was grafted as a free graft in 20 patients. The ITA graft patency rate was 96 per cent (67/70) at the time of hospital discharge. The operative morbidity included 3 reoperations for bleeding, 1 perioperative myocardial infarction, 1 renal failure, 2 postcardiotomy shock, and 1 colon perforation. Two hospital deaths occurred; one due to colon perforation and the other due to postcardiotomy cardiogenic shock. One patient died of cerebral infarction 6 month after the operation. Thirty-four patients were in New York Heart Association functional class I, 2 were in class II and 1 was in class III. Cardiac function evaluated by echocardiography and scintigraphy showed significant improvement postoperatively. These data suggest that the use of bilateral ITA grafts is associated with an acceptable mortality and increases the versatility of arterial grafting.

Aged↗